models/johnpye/solardynamics.a4c

REQUIRE "ivpsystem.a4l";
REQUIRE "atoms.a4l";
REQUIRE "johnpye/thermo_types.a4c";
REQUIRE "johnpye/datareader/testtmy3.a4c";
REQUIRE "johnpye/moltensalt.a4c";

(*
	This is a proof-of-concept test of a model for solar power plant
	dynamics in ASCEND. The system being modelled has a lossless solar thermal
	collector, a perfectly mixed storage tank, and a turbine that produces 
	electricity.

	The boundaries defined are
	(1) if solar GHI: > 300 W/m2, then the collector provides heat to the tank
	                  < 200 W/m2, then the collector switches off.
	(2) if the tank temperature: exceeds 550C, then turbine switches on
	                             drops below 400C, then turbine switches off.

	The data file mentioned below can be downloaded from 
	http://rredc.nrel.gov/solar/old_data/nsrdb/1991-2005/data/tmy3/723815TYA.CSV
*)
MODEL solardynamics;
	t IS_A time;
	INDEPENDENT t;

	(* Weather data reader *)
	dr IS_A tmy3;
	dr.tmydata.filename :== 'johnpye/datareader/723815TYA.CSV';
	dr.t, t ARE_THE_SAME;
	T_amb ALIASES dr.T;
	G ALIASES dr.GHI;
	(*
	T_amb IS_A temperature;
	G IS_A power_per_area;
	*)

	(* Solar collector *)
	C IS_A factor;
	A IS_A area;
	Qdot_abs IS_A energy_rate;
	col_on: Qdot_abs = C*A*G;
	col_off: Qdot_abs = 0;

	(* Storage *)
	m IS_A mass;
	TA IS_A moltensalt_fluid;
	h ALIASES TA.h;
	T ALIASES TA.T;
	DERIVATIVE OF h;
	Qdot_elec IS_A energy_rate;
	m * der(h) = Qdot_abs - Qdot_elec;

	(* Power block *)
	Wdot_elec, Qdot_elec_des IS_A energy_rate;
	eta IS_A fraction;
	(* power cycle efficiency: chambadal novikov efficiency *)
	eta = 1 - sqrt(T_amb / T); 
	Qdot_elec*eta = Wdot_elec;
	pow_on: Qdot_elec = Qdot_elec_des;
	pow_off: Qdot_elec = 0;

	(* Switching logic *)
	is_G_high, is_G_low, is_T_start, is_T_stop IS_A boolean_var;
	CONDITIONAL
		G_high: G > 300 {W/m^2};
		G_low: G < 200 {W/m^2};
		T_start: T > (550 {K} + 273.15 {K});
		T_stop: T < (400 {K} + 273.15 {K});
	END CONDITIONAL;
	is_G_high == SATISFIED(G_high);
	is_G_low == SATISFIED(G_low);
	is_T_start == SATISFIED(T_start);
	is_T_stop == SATISFIED(T_stop);
	ev1: EVENT (is_G_high)
		CASE TRUE: USE col_on;
	END EVENT;
	ev2: EVENT (is_G_low)
		CASE TRUE: USE col_off;
	END EVENT;
	ev3: EVENT (is_T_start)
		CASE TRUE: USE pow_on;
	END EVENT;
	ev4: EVENT (is_T_stop)
		CASE TRUE: USE pow_off;
	END EVENT;
METHODS
	METHOD obs_init;
		G.obs_id := 1;
		T_amb.obs_id := 2;
		T.obs_id := 3;
		Wdot_elec.obs_id := 4;
	END obs_init;
	METHOD specify;
		FIX C := 2000;
		FIX Qdot_elec_des := 1 {MW};
		FIX A := 2000 {m^2};
		FIX TA.p := 1 {bar};
		t := 0 {s};
		T := 300 {K} + 273.15 {K};
		is_G_high := FALSE;
		is_G_low := TRUE;
		is_T_start := FALSE;
		is_T_stop := TRUE;
	END specify;
	METHOD on_load;
		RUN specify;
		RUN obs_init;
	END on_load;
END solardynamics;
1	REQUIRE "ivpsystem.a4l";
2	REQUIRE "atoms.a4l";
3	REQUIRE "johnpye/thermo_types.a4c";
4	REQUIRE "johnpye/datareader/testtmy3.a4c";
5	REQUIRE "johnpye/moltensalt.a4c";
6
7	(*
8	This is a proof-of-concept test of a model for solar power plant
9	dynamics in ASCEND. The system being modelled has a lossless solar thermal
10	collector, a perfectly mixed storage tank, and a turbine that produces
11	electricity.
12
13	The boundaries defined are
14	(1) if solar GHI: > 300 W/m2, then the collector provides heat to the tank
15	< 200 W/m2, then the collector switches off.
16	(2) if the tank temperature: exceeds 550C, then turbine switches on
17	drops below 400C, then turbine switches off.
18
19	The data file mentioned below can be downloaded from
20	http://rredc.nrel.gov/solar/old_data/nsrdb/1991-2005/data/tmy3/723815TYA.CSV
21	*)
22	MODEL solardynamics;
23	t IS_A time;
24	INDEPENDENT t;
25
26	(* Weather data reader *)
27	dr IS_A tmy3;
28	dr.tmydata.filename :== 'johnpye/datareader/723815TYA.CSV';
29	dr.t, t ARE_THE_SAME;
30	T_amb ALIASES dr.T;
31	G ALIASES dr.GHI;
32	(*
33	T_amb IS_A temperature;
34	G IS_A power_per_area;
35	*)
36
37	(* Solar collector *)
38	C IS_A factor;
39	A IS_A area;
40	Qdot_abs IS_A energy_rate;
41	col_on: Qdot_abs = CAG;
42	col_off: Qdot_abs = 0;
43
44	(* Storage *)
45	m IS_A mass;
46	TA IS_A moltensalt_fluid;
47	h ALIASES TA.h;
48	T ALIASES TA.T;
49	DERIVATIVE OF h;
50	Qdot_elec IS_A energy_rate;
51	m * der(h) = Qdot_abs - Qdot_elec;
52
53	(* Power block *)
54	Wdot_elec, Qdot_elec_des IS_A energy_rate;
55	eta IS_A fraction;
56	(* power cycle efficiency: chambadal novikov efficiency *)
57	eta = 1 - sqrt(T_amb / T);
58	Qdot_elec*eta = Wdot_elec;
59	pow_on: Qdot_elec = Qdot_elec_des;
60	pow_off: Qdot_elec = 0;
61
62	(* Switching logic *)
63	is_G_high, is_G_low, is_T_start, is_T_stop IS_A boolean_var;
64	CONDITIONAL
65	G_high: G > 300 {W/m^2};
66	G_low: G < 200 {W/m^2};
67	T_start: T > (550 {K} + 273.15 {K});
68	T_stop: T < (400 {K} + 273.15 {K});
69	END CONDITIONAL;
70	is_G_high == SATISFIED(G_high);
71	is_G_low == SATISFIED(G_low);
72	is_T_start == SATISFIED(T_start);
73	is_T_stop == SATISFIED(T_stop);
74	ev1: EVENT (is_G_high)
75	CASE TRUE: USE col_on;
76	END EVENT;
77	ev2: EVENT (is_G_low)
78	CASE TRUE: USE col_off;
79	END EVENT;
80	ev3: EVENT (is_T_start)
81	CASE TRUE: USE pow_on;
82	END EVENT;
83	ev4: EVENT (is_T_stop)
84	CASE TRUE: USE pow_off;
85	END EVENT;
86	METHODS
87	METHOD obs_init;
88	G.obs_id := 1;
89	T_amb.obs_id := 2;
90	T.obs_id := 3;
91	Wdot_elec.obs_id := 4;
92	END obs_init;
93	METHOD specify;
94	FIX C := 2000;
95	FIX Qdot_elec_des := 1 {MW};
96	FIX A := 2000 {m^2};
97	FIX TA.p := 1 {bar};
98	t := 0 {s};
99	T := 300 {K} + 273.15 {K};
100	is_G_high := FALSE;
101	is_G_low := TRUE;
102	is_T_start := FALSE;
103	is_T_stop := TRUE;
104	END specify;
105	METHOD on_load;
106	RUN specify;
107	RUN obs_init;
108	END on_load;
109	END solardynamics;